<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        div{
            display: flex;/*给父盒子加上这句话，span元素才生效*/
            justify-content: space-between;/*flex项目，先左右贴边，再平分剩余的空间*/
            height: 300px;
            width: 100%;
            background-color: pink;
        }
        span{
            width: 100px;
            height: 100px;
            background-color: purple;
        }
    </style>
</head>
<body>
<!--在flex布局里，行内元素也能设置宽和高-->
  <div class="">
    <span></span>
    <span></span>
    <span></span>
  </div>
</body>
</html>